Which do you suppose would have a greater influence on your life and behavior:
(1) A firm, conscious belief in god that, nevertheless was not based on any personal experience, or
(2) An actual experience of god that, however, you somehow manage to consciously forget ever happened?
Why?
In option #1, I suppose you mean that you are raised and socialized into a belief, or that you come to your belief by studying religions and select the one that makes the most sense to you. This happens over a period of time, allowing you to integrate your beliefs into your life in various ways, even if you have no experiences to validate or relate to them.
In option #2, how much time elapses between the experience and forgetting? If you have the experience, and immediately after God pushes your "wipe memory" button, or your mind decides to bury the experience because it is so overwhelming to the conscious mind (think PTSD), I would suspect it would have little or no impact--although PTSD can be pretty severe--but that assumes it was an overwhelming and 'traumatic" experience. What if the experience is overwhelming, but the opposite of whatever "traumatic" is? Is there a syndrome for post-extremely-positive-experience-eustress? If you have time--days, weeks, years--to mull it over and incorporate the implications and your understanding into your life, and THEN you forget about it, I think it could be as influential or more influential than your prior belief.